Three chimpanzees will be inoculated with plasma or lymphocyte rich plasma from multiple patients in various stages of the AIDS spectrum. Large volumes will be utilized to simulate the human transfusion experience. Animals will be monitored for clinical and immunologic evidence of AIDS and will be screened for antibody seroconversion to HTLV-III, the postulated agent of AIDS. The study is aimed at proving the existence of a transmissible AIDS agent in human plasma and establishing an animal model for vaccine and other studies. In a second phase of this study, emphasis will be placed on establishing a reproducible disease model for AIDS. To induce clinical manifestations, conditions simulating the human experience will be employed, namely repeated inoculation of virus, coinfection with other viruses and immunologic stimulation and/or suppression. Immunostimulation will be in the form of foreign protein (human factor VII concentrates) and allogenic cells.